Method for preparing printing forms and the like for continuous patterns

ABSTRACT

A METHOD OF PREPARING PRINTING FORMS IS DISCLOSED WHEREIN TWO PHOTOGRAPHIC REPRODUCATIONS ARE SEQUENTIALLY MADE OF THE SAME TEMPLATE HAVING TWO SEPARATE PATTERNS THEREON EACH PATTERN HAVING CORRESPONDING EDGES THAT CAN BE POSITIONED IN EXACT COINCIDING REGISTER WITH THE OTHER THE PHOTOGRAPHIC REPRODUCTIONS ARE THEN MOUNTED BY MEANS OF COINCIDING COMMON PUNCHED HOLES IN PREDETERMINED POSITIONS IN AN APPARATUS FOR PRINTING THE PATTERN ONTO A PRINTED CYLINDER SUCH THAT THE FRONT EDGE OF ONE REPRODUCTION ISPOSTIONED IN AN EXACT COINCIDING REGISTER WITH THE REAR EDGE OF THE OTHER REPRODUCTION. A SUNSTANTIALLY INVISIBLE JOINT IS THEREBY FORMED BETWEEN THE FRONT AND REAR EDGES OF THE PATTERN PRINTED ONTO THE PRINTING CYLINDER. THE SEPARATED PATTERNS ARE FORMED BY FIRST COVERING ONE END OF A PATTERNMASTER OR REPORT PATTERN WITH A FILM IMPERVIOUS TO LIGHT RAYS THAT CAN AFFECT PHOTOGRAPHIC MATERIAL. A PLURALITY OF HOLES EXACTLY CORRESPONDING TO BUTTONS ON A TEMPLATE FOIL ARE PUNCHED THROUGH BOTH THE REPORT PATTERN AND THE FILM AND BOTH ARE THEN MOUNTED ON THE TEMPLATE FOIL. AFTER THE OTHER ENDOF THE REPORT PAATTERNS IS SECURED TO THE TEMPLATE FOIL THE ENDS OF THE REPORT PATTERN AND THE FILM HAVING THE HOLES IS CUT THROUGH BY A SUBSTANTIALLY WAVEFORMED CUT LINE, AND THE ENDS DENOTED THE MASK, ARE REMOVED WITHOUT DISTURBING THE POSITION OF DTHE PORTION OF THE REPORT PATTERN STILL AATTACHED TO THE TEMPLATE FOIL. THE FIRST PHOTOGRAPHIC REPRODUCTION IS MADE OF THE COMBINATION OF THE TEMPLATE FOIL AND THE ATTACHED REPORT PATTERN AFTER THE SECOND PORTION OF THE FILM HAS BEEN REMOVED. OF THE TEMPLATE FOILAND THE MASK WHICH HAS BEN REMOUNTEDON THE BUTTONS OF THE TEMPLATE FOIL, THE PREVIOUSLY ATTACHED PORTION OF THE REPORT PATTERN HAVING BEEN FIRST REMOVED.

Filed Sept. 30, 1971 Feb. 26, 1974 H. J. LUTHER 3,794,486

METHOD FOR PREPARING PRINTING FORMS AND THE LIKE FOR CONTINUOUS PATTERNS 4 Sheets-Sheet l Feb. 26, 1974 H. .1. LUTHER METHOD FOR PREPARING PRINTING FORMS AND THE LIKE FOR CONTINUOUS PATTERN;

4' Sheets-Sheet 2 Filed-Sept. so, 1971 'F/ae FIG? 5 Feb. 26, 1974 H. J. LUTHER 3,794,436

-METHOD FOR PREPARING PRINTING FORMS AND THE LIKE FOR CONTINUOUS PATTERNS Filed 'Sept/ 50, 1971 4 Sheets-Sheei 3 Feb. 26, 1974 H.J. LUTHER 3,794,435

METHOD FOR PREPARING PRINTING FORMS AND THE LIKE FOR CONTINUOUS PATTERNS Filed Sept. 30, 1971 4 Sheets-Sheet 4 FIG. 11

United States Patent r 3,794,486 METHOD FOR PREPARING PRINTING FORMS AND THE LIKE FOR CONTINUOUS PATTERNS Harald Johan Luther, Alingsas, Sweden, assignor to Misomex Akfiebolag, Hagersten, Sweden Filed Sept. 30, 1971, Ser. No. 185,248

Int. Cl. G03c 5/04 US. Cl. 96--37 4 Claims ABSTRACT OF THE DISCLOSURE A method of preparing printing forms is disclosed wherein two. photographic reproductions are sequentially made of the same template having two separate patterns thereon, each pattern having corresponding edges that can be positioned in exact coinciding register with the other. The photographic reproductions are then mounted by means of coinciding common punched holes in predetermined positions in an apparatus for printing the pattern onto a printed cylinder such that the front edge of one reproduction is positioned in an exact coinciding register with the rear edge of the other reproduction. A substantially invisible joint is thereby formed between the front and rear edges of the pattern printed onto the printing cylinder.

The separate patterns are formed by first covering one end of a pattern master or report pattern with a film impervious to light rays that can affect photographic material. A plurality of holes exactly corresponding to buttons on a template foil are punched through both the report pattern and the film and both are then mounted on the template foil. After the other end of the report pattern is secured to the template foil, the ends of the report pattern and the film having the holes is cut through by a substantially waveformed out line, and the ends, denoted the mask, are removed without disturbing the position of thevportion of the report pattern still attached to the template foil. The first photographic reproduction is made of the combination of the template foil and the attached report pattern after the second portion of the film has been removed. The second photographic reproduction is made of the template foiland the mask which has been remounted on the buttons of the template foil, the previously attached portion of the report pattern having been first removed.

The present invention refers to a method for preparing printing forms and the like for continuous patterns. By pattern in this connection is meant any type of design pattern which is so shaped that the front part thereof exactly corresponds as to its form and size to its rear part, so that unlimited long prints may be formed of the patterns following each other by means of a comparatively small size printing form or the like.

The invention may be executed within a great number of various fields, e.g. for preparing rotary print cylinders for letterpress printing, planographic printing or intaglio printing, for preparing round printing shablons or stencil (i.e. an endless stencil which can print an endless pattern) for silk screen printing, for multiple copying or so called reporting (i.e. repeating) of a small part of a pattern for obtaining a large continuous pattern, picture, for joining together more identical pattern films in order to obtain a large composite film, for joining together screen negatives, for repeating fiat printing plates or silk scree stencils and for many other things. 7

Continuous patterns are commonly used in the manufacture of Wall papers, fabrics, wrapping papers, wall and bench disks, imitation wood plates and of many other items, where the pattern is generally transferred to the base material by means of any printing method. The print- 3,794,486 Patented Feb. 26, 1974 ing usually takes place by means of rotary printing cylinders but may also take place by means of flat printing plates". In the latter method the printing takes place in successive steps with a mutual displacement between the printing plate and the base material in every step, the displacement exactly corresponding to the length of the pattern. 'It is obvious that in practice it is impossible when printingwith flat printing plates to completely hide the joint between the rear edge of one print and the front edge of the following print. Hence, prints have generally been made by means of rotary cylinders.

The preparation of rotary printing cylinders for this purpose however offers difficulties in obtaining a joint between the" front and rear edges of the pattern which is asinvisible as possible. Sometimes the joint may be completely hidden, as in the case where the pattern is of a type such that the joint may be located completely withinnon-printedpart of the pattern. Generally however, the joint of the pattern has to cut the image carrying parts in a great number of spots, and the solution to the problem in obtaining thereby a careful register between said image carrying partsout apart by the joint has previously been approached in many various ways. However no such solution'has provided a satisfactory result, and many attempts to solve the problem have proven to be too time consuming. Solutions which require wholly manual methods demand" the exercise of extremely great care and the use of ahighly skilled operator, yet nevertheless still produce a lessthan satisfactory result.

In the Swedish Pat. No. 310,606 there is however disclosed a mechanical method of joining together the front and rear edges of the pattern. According to said method an auxiliary foil is utilized which is attached directly to the pattern film and which is parted by a substantially sinusoidal line depending on the formation of the pattern. After the partition of said auxiliary foil one-half thereof is released and one part of the pattern is copied. There after the released half of the auxiliary foil is reattached to the pattern film as close tot he remaining first half of the auxiliary foil as possible, the said first half of the foil is released andthe copying of the pattern is continued until the whole pattern has been copied. In this method the rear edge of the pattern will be formed in correspondence to the first half of the auxiliary foil, while the front edge of the pattern which consequently is to'be joined with the rear edge will be formed in correspondence to the second half of the auxiliary foil. It may however happen that the two halves of the auxiliary foil have slight differences in the partition line in spite of the fact that they are cut through by'a common cut. Such differences may appear as a visible joint in the ready copied printing cylinder. In addition, difficulties may arise while applying the half of the auxiliary foil firstly released in careful register with the half of the auxiliary foil still existing'on the pattern, both depending on the difficulty of manually joining the two halves of the foil, such that no overlaps of spaces appear between them, and the fact that significant stretchings or shrinkages may arise in the two foil halves during the period when one of the foil halves is released from the' pattern film. Such stretchings or shrinkages appear as imperfect register in the outer edges of the joined pattern.

- The present invention is intended to avoid the deficiencies and disadvantages in the prior methodsand comprises a method and an arrangement, in which, as in the above mentioned Swedish Pat. No. 310,606, an auxiliary foil is appliedto the pattern film and is cut through by a bowformed out line at a location depending on the formation:of the pattern, but in which only one-half of the auxiliary foil is utilized for forming thewave formed joint line in-both' the front edge and the rear edge of the pattern, whereby any risk of imperfect register due to differlines is eliminated, and in which the joining of the front and rear edges of the pattern against each other automatically takes place with an extremely accurate register.

Further characteristics of the invention will be evident from the following detailed description, in which reference will be made to the accompanying drawings, and from the attached claims.

In the drawings FIGS. 1 through 5 schematically illustrate the first step in the method according to the invention in which a pattern film intended to be copiedonto a printing cylinder is prepared, and FIG. 6 schematically shows the second step in the method according to the invention, in which the pattern film thus prepared is copied to a printing cylinder. FIG. 7 illustrates a modified embodiment of the copying means schematically indicated in FIG. 6. FIG. 8 shows in an enlarged scale a detail of the arrangement of FIG. 7, and FIG. 9 is a cross section through the detail of FIG. 8, taken on line IXIX in FIG. 10. FIG. 10 illustrates a part of the detail of FIG. 8 in a side view, and FIG. 11 schematically shows a further detail of the arrangement according to FIGS. 7l0.'

In executing the invention a pattern copy formed in the conventional manner is utilized, and said pattern copy may consist of a photographic film on which the pattern images may appear positive or negative depending on the printing method for which the printing cylinder to be prepared is intended. The pattern copy is usually formed by copying together or so called reporting of a small size pattern in two directions perpendicular to each other for obtaining a composite pattern which is longer than the circumference of the printing cylinder in question. The pattern draft is likewise formed in the conventional manner, so that the rear edge of the report pattern exactly corresponds in its form and size to the front edgethereof, which is a pre-requisite in order to obtain an invisible joint, Further the composite report pattern thus formed must be prepared in such a scale that the periphery-of the printing cylinder to be prepared forms a whole multiple of the pattern draft since otherwise a space or an overlap may appear between the front and rear edges of the pattern. i

The production of the pattern film to be copied down onto the printing cylinder follows in the following manner. The report pattern 1 indicated in FIG. 1 is covered at one edge thereof with a colored film 2 having a color.

which does not transmit those light rays which affect the photographic material. Preferably an orthochromatic photographic material is used in the; present methodand at suitable spots. The. report pattern 1 is then released from the attachmentbuttons 5 of the templet foil 4 and is turned over as indicated with the dotted lines in FIG. 2, and the report pattern land the colored film 2 is cut through by a cut '8. Experience shows that a wave-formed joint is more difiicult to observe than a straight joint and for this reason the cut8 is made substantially sinusoidally. The cut is located as far as possible near the border'of the non-image'carrying parts of the pattern. The report pattern 1 which is still attached tothe templet foil 4 is turned back and the part 9 of the pattern which has been parted by the cut 8 is kept for use later on, the remaining part of the colored film 2 on the report pattern 1 is released from the pattern, and the pattern may be copied down onto a photographic film material.

The copying of the report pattern may be accomplished either by contact copying or by photography using a camera adjusted to a scale such that the report pattern of the ready prepared pattern film will form a whole multiple of the circumference of the printing cylinder. At the copying of the report pattern onto the film material 10 a blackening is obtained of all parts located outside the pattern except for the attachment buttons 5 of the templet foil 4, which form white circles, and the register marks 6 of the templet foil 4, which are reproduced as negative register marks. After the report pattern has been copied down onto the photographic film 10 the report pattern 1 is removed from the templet foil 4 and the part 9 thereof which was previously removed is applied together with the colored film, the mask pattern, which'is still present on said part 9, to the attachment buttons 5 of the templet foil 4. Without changing the adjustment of the camera a further exposure is made on another photographic film 11. The colored film 2 on the mask 9 prevents any affecting light rays from penetrating the colored film 2 and blackening will only take place of the parts of the film 11 located around the mask 9 and in the register marks 6.

in such case the color of the film 2 is red. The report pattern 1 thus provided with a colored film 2 at one edge is then provided with a number of punch holes 3 located at the edge of the colored film, the purpose of said punched holes being both to provide an attachment means for the report pattern 1 and the colored film 2 and to provide holes for register marks as will be further explained below. The report pattern 1 is then applied to a templet foil 4 comprising a translucent foil made from a material which is substantially free from shrinkage and stretching, and which at one edge thereof is provided with a number of attachment buttons 5 having a size and location corresponding to the punched holes 3 of the report pattern 1. When the report pattern 1 has been applied to the attachment buttons of the templet foil the pattern and the foil form a unit in which they are fixed in a stable position relative to each other. Close to the outer edge of the templet foil 4 and on line with the attachment buttons 5 there is provided at least two register marks 6 each corresponding to a punched hole 3 extending through the report pattern 1 and the colored film 2. The purpose of said register marks 6 will be explained below. The free end of the report pattern 1 is thereafter attached to the templet foil 4 by means of pieces of tape 7-placed Now there are two pattern films, that is the 10 on which the pattern appears in the form of light images and the film 11 on which the mask 9 has been reproduced in the form of a light image. It should be noted, that the Wave-formed right-hand edge which is called the front edge 12 is an exact reproduction of the cut line 8 of FIG. 2 and that the wave-formed edge 12 of the'mask film 11 likewise is an exact reproduction of the out line 8. The wave-formed edges of the pattern film 10 as well as the mask film 11 are consequently completely identical. It should also be noted, that the register marks on the pattern film 10 constitute a reproduction of the register marks 6 of the templet foil 4 and that the register marks on the mask film 11 likewise constitute a reproduction of the register marks 6 of the templet foil 4. The register marks and the wave-formed cut line of the pattern film 10 and of the mask film 11 therefore exactly correspond to each other, which means that the wave-formed edges 12 of the pattern film and the mask film will exactly correspond to each other when the mask film 11 is applied with its register marks above the register marks of the pattern film 10.

For facilitating further handling the mask film 11 is put onto the pattern film 10 so that the register marks coincide with each other, and the two films 10 and 11 are simultaneously provided with punch holes 13, which thus exactly coincide with each other.

The copy printing of the pattern onto the printing cylinder to be prepared may now get started and for this purpose an arrangement is utilized in which two embodiments are shown schematically in FIGS. 6 through 11. The arrangement according to FIG. 6 comprises a carrier which is not shown in the drawings, in which carrier the printing cylinder 14 may be mounted on pivot pins 15. The printing cylinder 14 in a conventional manner is provided with a cover of a light sensitive layer which may be tanned by means of short-wave light beams so as to be made non-soluble. Around the cylinder 14 a screen pattern 16 is resiliently mounted but said screen pattern 16 may if desired be omitted or replaced with a transparent film. A lighting means 17 for short-wave light is mounted above the printing cylinder 14, which is so formed that it will emit a narrow beam of light acros the entire length of the cylinder 14. Aside of the cylinder there is an application means comprising a mounting border 18, which is pivotally hinged adjacent to the periphery of the cylinder 14 with hinges 19. The mounting border is at least as long as the longest printing cylinder to be prepared and the width thereof is slightly less than the radius of the printing cylinder. Mounted at the non-hinged end of mounting border 18 are upwardly extending location pins 20, which correspond in their size and disposition to the punch holes 13 of the pattern film and the mask film 11. The arrangement further includes register means not shown in the drawings, but which are well known, and the function and action of which will be evident from the following description.

When print copying the pattern onto the printing cylinder 14 the pattern film 10 is threaded between the hinges 19 of the mounting border 18 and along the upper side of the border 18 and is attached to the location pins 20 by means of the punch holes 13. In order to obtain a better correspondence of the film 10 against the upper edge of the mounting border 18 said border may be provided with vacuum means for sucking the film firmly onto its upper edge. The border 18 is then rotated from the position indicated (A) to the position indicated (B) in FIG. 6, in which position the mounting border is forced against the cylinder 14, with, for example, the aid of spring pressure. The lower edge of the film 10 is attached to the screen pattern 16 by means of tape or the like and the upper edge of the film 10 is then released from the location pins 20 and is attached to the surface of the cylinder 14 by means of tape or the like. Since the mounting border 18 is forced against the cylinder 14 the film 10 may be released from the location pins 20 without moving the film 10 out of its fixed position with respect to the cylinder 14. After the front edge of the pattern film 10 has been fixedly mounted onto the screen pattern 16 on. the peripheral surface of the cylinder 14 the mounting border 18 is rotated back. At this point the cylinder 14 is in a O-position or starting position, which is located such that .a light beam emitted from the lighting means 17 will fall entirely within the mask at the front edge of the pattern film 10. At this position the front edge 12 of the pattern film 10 may be located about 40 millimeters in front of the, lighting means 17. The print apparatus is now started, whereby the said register means which is not shown in the drawings causes the cylinder 14 to rotate at the same time as the lighting means is turned on, and an exposure takes place of the printing cylinder through the pattern film 10. The register means stops the cylinder 14 and turns off the lighting means at the point when the cylinder 14 has rotated exactly one turn, i.e. when the cylinder has regained its O-position or starting position, and the waive-formed rear edge of the pattern film 10 is thus located about 40 millimeters in front of the lighting means 17. The mask film 11 is mounted on the location pins 20 in the same way as described above with respect to the pattern film 10, the mounting border 18- is rotated up so that the mask film 11 is attached between the border 18 and the cylinder 14, the mask film 11 is released from the location pins 20 and is attached by means of tape to the pattern film 10. The apparatus is now restarted by means of the register means, not shown, whereby the lighting means is once more turned on and the cylinder continues to rotate from the position in which the apparatus was previously stopped, and the exposure continues thereafter until the light beam emitted from the lighting means 17 falls entirely within the mask 11, which may means in practice that the wave-formed rear edge 12 of the pattern film 10 has passed the lighting means 17 by about 40 mm. Now a complete exposure has taken place through the pattern film 10. Since the pattern film 10 and the mask film 11 exactly coincide with each other with respect to the wave-formed edge 12 and the punch holes 13, and since both the pattern film 10 and the mask film 11 have been applied in the same manner and in exactly the same positions on the mounting border 18, viz, the 0-position, and in the same position on the cylinder 14, the wave-formed front edge of the pattern film 10 will exactly register with the wave-formed rear edge of the mask film 11. In other words there will be an exactly coinciding agreement between the front and rear edges of the pattern and with no overlapping or space between parts of the pattern. Furthermore, since the part of the mask film 11 following the wave-formed edge 12 is impervious to light of the kind which will affect the light sensitive layer of the cylinder 14, no double exposure or over-exposure can take place of said light sensitive layer even if the cylinder 14 has rotated so far that slightly more than the entire circumference of the cylinder has been exposed to light. Development, etching and any other treatments are then done in any conventional manner.

In FIGS..7 through 11 there is disclosed a modified embodiment of the apparatus shown in FIG. 6. The modified embodiment differs primarily from the above described embodiment in that the mounting border 18 has been replaced by a mounting roller 21 which basically acts in the same way as the border 18. As is best seen from FIG. 8 the mounting roller 21 is mounted in two yokes 22 which in turn are pivotally mounted about an axle 23 located in the base frame which also supports the cylinder 14. The free ends of yokes 22 are provided with grooves 24 which open towards said ends for detachable mounting mounting roller 21. At least one of the yokes 22 is provided with a resiliently mounted pin 25 located level with grooves 24 for resiliently engaging a corresponding bore 26 in the pivot pin of the roller 21. The spring pin 25 and the bore 26 form a fixed coupling of the mounting roller 21 in an exact predetermined position in relation to the yokes 22 and thereby in relation to the printing cylinder 14. Along an axial peripheral line of the mounting roller 21 there is provided a number of location pins 27 which coincide as to their size anddisposition with thepunch holes 13 of the pattern film 10 and the mask film 11. The location pins 27 are urged radially outward fromcylinder 14 by springs 28 and may be-depressed into cylinder 14 so as to be on line with the periphery of thecylinder 14. For establishing a steady mounting of the pattern film 10 and the mask film 11 along the roller 21 there is provided vacuum means for attaching thev films. Said vacuum means comprises a suction tube 29 extending axially within the cylinder 14 adjacent the periphery thereof and communicating with the exterior outside the cylinder 14 through holes 30 provided along an axial line of the periphery of the cylinder. The holes 30 are provided on the side of the location pins 27 of the roller 21 which is turned to the cylinder 14, are locatedat an angle of about 25 along the periphery of cylinder 21 from the location pins 27. The suction tube 29 may be rotated to at least two positions, -a first position in which vacuum acts through the holes 30 and a second position in which the holes 30 are cut ofi' from communication with the suction tube. In a modified embodiment of the invention the vacuum means has been adapted for various sizes of pattern films, and the vacuum means is so formed that a large number or a small number of holes 30 may alternatively be brought into communication with the suc tion tube 29 counted from the longitudinal center of the roller 21. In FIG. 11 such an arrangement is shown, the figure illustrating the envelope surface of the suction tube 29 extended in a plane. In the embodiment shown in FIG. 11, suction tube 29 includes 6 various adjustment positions numbered I through VI. In the position I the suction tube 29 is completely cut oil from communication 7 with the holes 30, while in the position VI the tube 29 is formed with 10 holes 31 each corresponding to one hole 30 of the roller 21. In the positions II-V the two, four, six and eight innermost holes respectively are in communication with corresponding holes 30 of the mounting roller 21. The suction tube 29 is sealingly mounted in a corresponding recess adjacent the periphery of the mounting roller 21 and in the conventional manner it is connected to a source of vacuum by means of a flexible conduit. In order to prevent damage to the pattern film 10 and the mask film -11 and to establish a good friction joint between the films and the roller the latter is covered with a comparatively soft synthetic resin or the like.

The copy printing of the pattern film 10 onto the cylinder 14 occurs basically in the same way as in the above described embodiment according to FIG. 6. The pattern film 10 is mounted with its punch holes 13 on the location pins 27 of the mounting roller 21 while the roller is in the position marked (A) in FIG. 7. The suction holes 30 are put under vacuum so as to pull the film steadily against the roller 21, and the roller is pivoted into engagement and resilient biassing against the printing cylinder 14. The spring pin 25 is released and the whole unit is rotated backwardly as indicated with the arrow C until the location pins 27 of the mounting roller 21 are brought into engagement radially with the periphery of the cylinder 14. At that point the pattern film 10 is released from the location pins 27 and the pattern film is attached by means of tape in the upper edge thereof to the screen pattern 16. It is also possible to attach in advance a double sticking tape along the upper edge of pattern film 10 which provides the advantage that the film 10 will automatically become fixed to the screen pattern when the unit has been moved backwards a sulficient long amount.

The machine is then started and a register means which is not shown in drawings but which is well known turns on the lighting means 17 at a predetermined O-pcsition and an exposure takes place of the cylinder 14 while rotating until only a short distance is left before the entire cylinder has been exposed to the lighting. At that moment the register means automatically turns off the lighting means. The mounting roller 21 has up to this point forced the pattern film 10 and the screen pattern 16 into engagement with the cylinder 14 so as to secure a safe contact between the film and the cylinder. In the position now reached the mounting roller 21 is repivoted from its position denoted B to its original position A and the roller is locked by means of the spring pin 25 in its mounting position. The mask film 11 is mounted on the pins 27 and the film is put under vacuum and the roller 21 is once again brought into contact with the cylinder 14. It should be noted that the cylinder 14 with the aid of the register means was previously brought to stop in the exact position, in which the pattern film 10 was mounted and consequently the mask film 11 will be positioned in exactly correct position in relation to the pattern film 10 since the wave-formed edges and the punch holes 13 of the films 10 and 11 exactly coincide with each other. The apparatus is now moved backwards in the same way as described above and the mask film 11 is attached to the pattern film 10 by means of tape in both the rear edge and the front edge whereupon the apparatus is started and the cylinder once again begins to rotate. By means of the said register means the lighting means 17 is once again turned on in exactly the same position of the cylinder 14, in which it was previously turned off and the exposure follows until the entire cylinder has been exposed to the light. Development and etching etc. is finally accomplished in the usual way.

It should be noted that even if only the preparation of cylindrical printing forms as described above the method according to the invention is as useful for preparing fiat printing forms, and it is obvious to one skilled in the art that the illustrated and above described apparatus for executing the method also may be utilized or easily modified for use in connection with fiat or flexible printing forms. It is to be understood that the above described and shown method and apparatus is not restricted to the chosen forms of execution, but all kinds of various modifications may be made Within the scope of the following claims.

What is claimed is:

1. A method of preparing printing forms for continuously extending patterns comprising covering one end of a report pattern with a film impervious to light rays that can affect photographic material, punching a plurality of holes through both said report pattern and said film, mounting said report pattern and said film to one end of a templet foil by means of attachment buttons provided in said holes and in said templet foil and attaching said report pattern to the other end of said templet, cutting said film and said report pattern by a substantially waveformed cut line, thereby providing a mask portion which comprises the portions of said report pattern and said film having said plurality of holes therein, and providing a second portion comprising the end of said report pattern attached to said other end of said templet and the other end of said film, removing said other end of said film from the portion of said report pattern attached to said templet foil, removing said mask-from said templet foil so as to prevent changing the position of that part of said second portion attached to said templet foil, making a photographic reproduction of the combination of said templet foil and that part of said second portion attached to said templet foil, said reproduction being denoted the pattern film and the reproduction of the edge made by said cut line being denoted the wave-formed front edge, removing said portion of said report pattern attached to said templet foil from said templet foil, remounting said mask on said templet foil by means of said holes, making a photographic reproduction of said mask and said templet foil, said reproduction being denoted the mask film and the reproduction of the edge made by said cut line being denoted the wave-formed rear edge, placing said pattern film and said mask film into exactly coinciding pattern register and punching coinciding corresponding holes in said pattern film and said mask film, mounting by means of the coinciding corresponding punched holes in predetermined positions in an apparatus for printing the pattern onto a printed cylinder such that the resulting wave-formed front edge of said pattern film is positioned in an exact coinciding register with the wave-formed rear edge of said mask film, thereby forming a substantially'invisible joint between the front and rear edges of the pattern.

2. A method according to claim 1 including providing said templet foil with register masks colinear to said attachment buttons for facilitating proper alignment of said pattern film and said mask film.

3. A method according to claim 2 including attaching said pattern film with attaching means mounted on a mounting means of a print copy apparatus, said print copy apparatus further having a printing cylinder, adjusting said printing cylinder to a predetermined zeroposition, bringing said mounting means into contact with said printing cylinder, releasing said pattern film from said attaching means and fixedly mounting said pattern film to said printing cylinder, rotating said printing cylinder an exact predetermined distance, attaching said mask film with said attaching means, bringing said mounted means into contact with the printing cylinder, releasing said mask film from said attaching means and fixedly mounting said mask film on said pattern film, said wave-formed front edge of said pattern film being in exact register with said wave-formed rear edge of said mask film, and reproducing the images of said mask film and said pattern film on said printing cylinder.

4. A method according to claim 1 including attaching said pattern film with attaching means mounted on a mounting means of a print copy apparatus, said print copy apparatus further having a printing cylinder, ad-

justing said printing cylinder to a predetermined zero- 5 position, bringing said mounting means into contact with said printing cylinder, releasing said pattern film from said attaching means and fixedly mounting said pattern film to said printing cylinder, rotating said printing 'cylinder an exact predetermined distance, attaching said mask film with said attaching means, bringing said mounted means into contact with the printing cylinder, releasing said mask film from said attaching means and fixedly mounting said mask film on said pattern film, said References Cited UNITED STATES PATENTS OTHER REFERENCES German printed application G15,811 IV a/57d, January 1956, Hicke Thier, 1 sheet drawing, 3 pp. spec.

wave-formed front edge of said pattern film being in 15 DAVID KLEIN, P i y Examiner exact register with said wave-formed rear edge of said mas-k film, and reproducing the images of said mask film and said pattern film on said printing cylinder.

US. Cl. X.R.

33-1845; 96-41; 101-Dig. 12; 35585 

